docs: Explain how integration tests work

docs/contributing/testing.rst

@@ -0,0 +1,34 @@
+Testing the client
+==================
+
+Every feature of a codebase must be tested if we want to be more confident about it.
+Tests help to document what the code does and how it works. Need a new feature or need to change
+the behavior of a current function? Tests are here to cover you.
+
+Integration tests
+-----------------
+
+The purpose of an Integration test is to ensure that our code units, depending on other units, work as expected.
+In our case, we need to test how our code behave when interacting to the real API. How does it handle real JSON responses?
+
+To acomplish this task, we use `Betamax <https://github.com/betamaxpy/betamax>`_ library. It records real requests made to the API,
+saves it as JSON and replays it next time, without hitting the production site again.
+
+Here is an example on how to test the creation of a new configuration:
+
+.. code-block:: python
+
+    class TestConfiguration(object):
+
+        def test_create_configuration(self):
+            client = Azion(token)
+            recorder = betamax.Betamax(client.session)
+
+            with recorder.use_cassette('Configuration_create'):
+                configuration = client.create_configuration(
+                    'Dummy configuration', 'www.example.com', 'ww2.example.com',
+                    cname=['www.example-cname.com'], delivery_protocol='http')
+            assert isinstance(configuration, Configuration)
+
+`Cassettes` are the files used to store/load requests and responses. A good convention is to name them with the resource capitalized
+and the action of the API function in lowercase, for example: ``Configuration_create``

docs/index.rst

@@ -49,6 +49,14 @@ API
 
     api/index
 
+Contributing
+============
+
+.. toctree::
+    :maxdepth: 2
+
+    contributing/testing
+
 Indices and tables
 ==================